Skin Anatomy

Our eyes provide a way to gather information about our environment and send it to our brain for processing. The eyelids protect the eyes from injury, control the amount of light that enters the eye, and lubricate the eyeball with tears secreted by the lacrimal gland during blinking. All these functions together help maintain the structural integrity of the eyeball and protect them from external influences.

The eyelid consists primarily of skin, underlying subcutaneous tissue, and a thin layer of muscle called the orbicularis oculi. Under this muscle are the septum and the tarsi. Lid retractors assist us in blinking. The eyeball is covered by a thin layer of tissue called the conjunctiva.

Anatomy of the eyelid

From a more detailed perspective, a sagittal section can provide more information about eyelid structure. Tissues can be divided into planes by structures called the orbital septum, which differentiates the orbital tissue from the lid. Behind the septum are the anterior and posterior lamellae: the anterior lamella consists of the skin and the orbicularis oculi muscle while the posterior lamella consists of the conjunctiva and the tarsus.

SKIN CANCER/SUNSCREEN FACTS

Primarily we are surgeons. Idaho Eyelid and Facial Plastic Surgery focuses on both functional repairs as well as elective cosmetic surgeries in Boise, Idaho. Regardless of the type of procedure, we want our patients to do their best to prevent skin cancer, protect their investment, and maintain results. Patients should protect their skin against harmful ultra violet rays by applying a broad-spectrum sunscreen with sun protection factor (SPF) 30 or higher every day to prevent sun damage and premature aging.

More depth of understanding is needed in relation to UVA and UVB. UVB causes a “burn appearance” and is most prevalent on sunny days from 10:00 am to 2:00 p.m. The UVB frequency range should cover 280 to 400 nanometers, and the greatest concern lies between 290 and 360 nanometers. DNA damage does occur in the UVB spectrum. SPF addresses the time it takes for your skin to burn. The number signifies, in general, period of time that it takes the average Caucasian skin to burn with sun screen versus no sun screen.

Some important information to consider about UVA and UVB:

• A suntan lotion can offer 99% UVB protection and minimal UVA absorbency, yet it is classified as “broad spectrum” in the United States.
• SPF only relates UVB and has nothing to do with UVA radiation; UVA radiation causes “aging appearance.”
• UVA exists in rain or shine from sunrise to sunset 365 days a year.
• UVA causes long term damage that may possibly not appear for years.
• UVB and UVA radiation are both known to cause skin cancer.
• Because SPF rating does not acknowledge the specific amount of absorption in the UVB range and the FDA does not have a monograph for UVA production, there is no definitive measure in the United States to assess the efficacy of a sunscreen product for UVA and UVB production.

Most sunscreens contain both physical and chemical ingredients. Physical sunscreens work like reflective barriers and scatter the UV rays before they penetrate your skin (titanium and since oxides, for example). Chemical filters absorb the UV rays and change them into heat before they damage the skin. When selecting a sunscreen, keep the following in mind:

• Some people with more sensitive skin prefer physical sunscreens as they are often less irritating.
• Use at least SFP 30 if your sun exposure is more than a few minutes outside.
• It takes some time for ingredients to work, so apply 30 minutes prior to sun exposure. Many sunscreens break down within hours and must be reapplied often (every two hours).
• Most adults need at least an ounce of sunscreen to protect their face, arms, legs, and neck.
• Use hats, shade, and UV protected clothing as well.
• Sunglasses are very important to protect eyeballs from UV rays.
• Idaho Eyelid and Facial Plastic Surgery recommends two sunscreen lines available for purchase (Epionce and Obagi lines).